Tonofibril (Tonofibril)

Tonofibril is a set of protein filaments that are found in the cytoplasm of epithelial cells. They have a fine structure and play an important role in maintaining the shape and function of these cells.

Tonofibrils were first discovered in 1951 in human skin epithelial cells. They are bundles of protein filaments, consisting mainly of keratins - the main protein components of epithelial cells. In addition, they may contain myosin, actin and other proteins.

One of the main functions of tonofibrils is to maintain the mechanical stability of epithelial cells. Bundles of tonofibrils are rigidly attached to the cytoplasmic sides of both plates of desmosomes - cellular junctions that provide strong adhesion between cells in epithelial tissue.

In addition, tonofibrils may play a role in transporting substances within the cell. They can serve as a “railway” for various molecules and organelles, moving them in the right direction.

Despite the fact that tonofibrils were discovered more than half a century ago, little is still known about the mechanisms of their formation and regulation. However, studying their structure and functions can lead to new discoveries in the field of biomedicine, for example, in the development of new methods for treating diseases associated with defects in epithelial tissues.

Thus, tonofibrils are an important element of the cytoskeleton of epithelial cells, ensuring their mechanical stability and participating in the transport of intracellular components. Despite the fact that research in this area continues, it can already be said that tonofibrils are a unique and interesting structure that deserves further study.

Tonofibrils: from name to structure

Tonofibrils are thin protein fibers that are present in the cytoplasm of some epithelial cells and form bundles. They are attached to the cytoplasmic side of desmosomes, but are not part of them. Desmosomes are intercellular junctions that provide connections between cells in epithelial tissues such as skin, mucous membrane, etc.

The name “tonofibrils” comes from the Greek words “tonos”, meaning “thin thread”, and “fibros”, meaning “fiber”. Tonofibrils really resemble thin filaments that form bundles in the cytoplasm of cells.

Functions of tonofibrils

The main function of tonofibrils is to provide mechanical support and stability to cells in epithelial tissue. They serve as a framework for the cytoplasm and provide structural stability to cells, preventing their deformation and rupture. In addition, tonofibrils are involved in the transmission of signals between cells, for example, during the processes of cell growth and division.

Tonofibrella, or myosin filaments of the cytoskeleton.

*Tonofibrils are protein structures that perform many important functions in the body. They are thin, flexible bundles of protein molecules called filaments.*

1. Tonofibilla are clearly visible in a light microscope during the electromechanical coupling process as thin threads. Present in tropomyosin thick filaments of the tiger body membrane, where they also interact with kinesin of muscle fibers [38].

2. Tonofabbles were first discovered in the myocardial muscles of the Wheat rat when it was discovered that they were associated with the epithelonemal line on the surface of the heart muscle, and were called T-filaments. Subsequently, it turned out that these tonophobes provide a connection between muscle tissue and connective tissue. This interaction between muscles and connective tissue is called mechanical adhesion [39]

**How ​​the tonofisha is structured:** Under the epithelonelmal line, the muscle fibers of the muscular layer of the heart are penetrated by the tonofisha in different places. The places where the tonofibe penetrates are called the spaces of the intimal line - the intimal interstitium, where the tonofibe penetrates with its ends, connecting to the muscle layer and filling it between the places of attachment. Thus, the tutokon is fixed between the two tissues and prevents complete rupture. In addition to tonophycils, in these